Apparatus and method for creating inferential process flow measurements using other process measurements

Abstract

A method includes obtaining actual flow measurements generated by a flow meter, where the actual flow measurements identify a flow of material in a passageway. The method also includes generating estimated flow measurements based on process variable measurements other than the actual flow measurements. The method further includes comparing the estimated flow measurements and the actual flow measurements and determining whether a problem exists based on the comparison. The estimated flow measurements could be generated using one or more models mathematically representing how the flow of material in the passageway relates to non-flow process variables associated with the process variable measurements. The process variable measurements could be obtained from one or more sensors associated with a flow restrictor in the passageway, one or more sensors positioned within the passageway, and/or one or more sensors positioned outside the passageway.

What is claimed is: 
     
       1. A method comprising:
 obtaining actual flow measurements generated by a flow meter, the actual flow measurements identifying a flow of material in a passageway, wherein the actual flow measurements are obtained at a specified interval, all at once or at another time; 
 generating estimated flow measurements based on process variable measurements other than the actual flow measurements, wherein the process variable measurements other than the actual flow measurements comprise non-flow measurements that have a relationship to the flow of material in the passageway; 
 comparing the estimated flow measurements and the actual flow measurements; and 
 determining whether a problem exists based on the comparison. 
 
     
     
       2. The method of  claim 1 , wherein the process variable measurements comprise process variable measurements from one or more sensors associated with a flow restrictor in the passageway, wherein the flow restrictor comprises a structure having a fixed opening or a variable opening that is narrower than a surrounding structure, wherein the flow restrictor comprises at least one of a: flow orifice, an orifice plate and a pipe fitting. 
     
     
       3. The method of  claim 1 , wherein the process variable measurements comprise process variable measurements from one or more sensors positioned within the passageway. 
     
     
       4. The method of  claim 1 , wherein the process variable measurements comprise process variable measurements from one or more sensors positioned outside the passageway, wherein the one or more sensors comprises at least one of the following types of sensors: a mechanical sensor, an optical sensor, an open-channel sensor, a thermal mass sensor, a vortex sensor, a sonar sensor, an electromagnetic sensor, an ultrasonic sensor, a Coriolis sensor, and a laser Doppler flow meter. 
     
     
       5. The method of  claim 1 , wherein determining whether the problem exists comprises determining whether the estimated flow measurements differ from the actual flow measurements by a threshold percentage for a specified amount of time. 
     
     
       6. The method of  claim 1 , wherein generating the estimated flow measurements comprises using one or more models mathematically representing how the flow of material in the passageway relates to non-flow process variables associated with the process variable measurements. 
     
     
       7. The method of  claim 1 , further comprising, in response to determining that the problem exists, at least one of:
 generating a warning or an alarm; 
 updating one or more parameters used to generate the estimated flow measurements; and 
 using the estimated flow measurements in place of the actual flow measurements to control an industrial process. 
 
     
     
       8. An apparatus comprising:
 at least one processing device configured to:
 obtain actual flow measurements generated by a flow meter, the actual flow measurements identifying a flow of material in a passageway wherein the actual flow measurements are obtained at a specified interval, all at once or at another time; 
 generate estimated flow measurements based on process variable measurements other than the actual flow measurements, wherein the process variable measurements other than the actual flow measurements comprise non-flow measurements that have a relationship to the flow of material in the passageway; 
 compare the estimated flow measurements and the actual flow measurements; and 
 determine whether a problem exists based on the comparison. 
 
 
     
     
       9. The apparatus of  claim 8 , wherein the process variable measurements comprise process variable measurements from one or more sensors associated with a flow restrictor in the passageway, wherein the flow restrictor comprises a structure having a fixed opening or a variable opening that is narrower than a surrounding structure, wherein the flow restrictor comprises at least one of a: flow orifice, an orifice plate and a pipe fitting. 
     
     
       10. The apparatus of  claim 8 , wherein the process variable measurements comprise process variable measurements from one or more sensors positioned within the passageway. 
     
     
       11. The apparatus of  claim 8 , wherein the process variable measurements comprise process variable measurements from one or more sensors positioned outside the passageway, wherein the one or more sensors comprises at least one of the following types of sensors: a mechanical sensor, an optical sensor, an open-channel sensor, a thermal mass sensor, a vortex sensor, a sonar sensor, an electromagnetic sensor, an ultrasonic sensor, a Coriolis sensor, and a laser Doppler flow meter. 
     
     
       12. The apparatus of  claim 8 , wherein, to determine whether the problem exists, the at least one processing device is configured to determine whether the estimated flow measurements differ from the actual flow measurements by a threshold percentage for a specified amount of time. 
     
     
       13. The apparatus of  claim 8 , wherein, to generate the estimated flow measurements, the at least one processing device is configured to use one or more models mathematically representing how the flow of material in the passageway relates to non-flow process variables associated with the process variable measurements. 
     
     
       14. The apparatus of  claim 8 , wherein the at least one processing device is further configured, in response to determining that the problem exists, to at least one of:
 generate a warning or an alarm; 
 update one or more parameters used to generate the estimated flow measurements; and 
 use the estimated flow measurements in place of the actual flow measurements to control an industrial process. 
 
     
     
       15. A non-transitory computer readable medium containing instructions that when executed cause at least one processing device to:
 obtain actual flow measurements generated by a flow meter, the actual flow measurements identifying a flow of material in a passageway wherein the actual flow measurements are obtained at a specified interval, all at once or at another time; 
 generate estimated flow measurements based on process variable measurements other than the actual flow measurements, wherein the process variable measurements other than the actual flow measurements comprise non-flow measurements that have a relationship to the flow of material in the passageway; 
 compare the estimated flow measurements and the actual flow measurements; and 
 determine whether a problem exists based on the comparison. 
 
     
     
       16. The non-transitory computer readable medium of  claim 15 , wherein the process variable measurements comprise process variable measurements from one or more sensors positioned within the passageway. 
     
     
       17. The non-transitory computer readable medium of  claim 15 , wherein the process variable measurements comprise process variable measurements from one or more sensors positioned outside the passageway, wherein the one or more sensors comprises at least one of the following types of sensors: a mechanical sensor, an optical sensor, an open-channel sensor, a thermal mass sensor, a vortex sensor, a sonar sensor, an electromagnetic sensor, an ultrasonic sensor, a Coriolis sensor, and a laser Doppler flow meter. 
     
     
       18. The non-transitory computer readable medium of  claim 15 , wherein the instructions that when executed cause the at least one processing device to determine whether the problem exists comprise:
 instructions that when executed cause the at least one processing device to determine whether the estimated flow measurements differ from the actual flow measurements by a threshold percentage for a specified amount of time. 
 
     
     
       19. The non-transitory computer readable medium of  claim 15 , wherein the instructions that when executed cause the at least one processing device to generate the estimated flow measurements comprise:
 instructions that when executed cause the at least one processing device to use one or more models mathematically representing how the flow of material in the passageway relates to non-flow process variables associated with the process variable measurements. 
 
     
     
       20. The non-transitory computer readable medium of  claim 15 , further containing instructions that when executed cause the at least one processing device, in response to determining that the problem exists, to at least one of:
 generate a warning or an alarm; 
 update one or more parameters used to generate the estimated flow measurements; and 
 use the estimated flow measurements in place of the actual flow measurements to control an industrial process.